Photobleaching of protoporphyrin IX in cells incubated with 5-aminolevulinic acid.

@article{Moan1997PhotobleachingOP,
  title={Photobleaching of protoporphyrin IX in cells incubated with 5-aminolevulinic acid.},
  author={Johan E. Moan and Giedre Streckyte and Saulius Bagdonas and O. Bech and Kristian Berg},
  journal={International journal of cancer},
  year={1997},
  volume={70 1},
  pages={90-7}
}
Protoporphyrin IX (Pp IX) is the main photosensitizer in photochemotherapy with 5-aminolevulinic acid (ALA). Pp IX is photolabile and the present work shows that 70-95% of Pp IX in cells is degraded by clinically relevant light exposures (40-200 J cm(-2) at 630 nm). During light exposure a small yield of photoprotoporphyrin, which is also photolabile, is formed. A substantial fraction of Pp IX in cells incubated with ALA is bound to proteins. During light exposure these binding sites are… CONTINUE READING